Among other things, Trump repeatedly criticized Christie for his embrace of US President Barack Obama after Hurricane Sandy devastated New Jersey in 2012. The photo-op rankled some Republicans at the time because it occurred right before Obama's reelection.

"I don't call it a hug, I call it a hug mentally. It was like — it was unbelievable," Trump added. "He was like a little boy: 'Oh, I'm with the president.' Remember he flew in the helicopter and he was all excited to be in the helicopter? I said, 'I would have put you in my helicopter. It's much nicer.'"

Earlier in the day, Trump explained that he was attacking Christie because he felt that the governor had colluded with the Union Leader on a scathing front-page editorial that opined, "Trump has shown himself to be a crude blowhard." The New Hampshire newspaper previously endorsed Christie.

Trump blasted Christie at his rally in the middle of a 10-minute-plus criticism of the Union Leader's publisher, whom Trump called a "loser," "lowlife," and "sleazebag." Trump said he couldn't believe that Christie earned the paper's endorsement because of his embrace of Obama in 2012 and his overall stewardship of the New Jersey economy.

"You've had tremendous downgrades — either nine or 11 — downgrades of the bonds," Trump said of the state's credit. "It's No. 50 out of 50 in terms of economic development and in terms of the economy. It's like one of the worst in the country for jobs. It's a disaster. I have property in New Jersey. The taxes are through the roof. They're through the roof."

Not stopping there, Trump hit Christie for the so-called Bridgegate scandal. Multiple Christie aides and appointees were accused of deliberately creating debilitating traffic around the base of the George Washington Bridge in 2013 in order to punish Fort Lee's mayor for not endorsing Christie's reelection campaign.

Christie was never accused of any wrongdoing, but Trump said he was unconvinced.

"Does anyone believe that?" he asked after incredulously acting out Christie's aides supposedly not telling their boss about the alleged plot. "Honestly, is there a 1% chance? And I've been friends with Christie."

New Jersey Gov. Chris Christie.
REUTERS/Eduardo Munoz

Trump finished his attack against Christie and the Union Leader by assailing Christie for not spending more time back home in New Jersey and flinging a print copy of the newspaper into his crowd of supporters.

"You can have it, darling," Trump said to an audience member. "That's all it's worth. A piece of garbage."

Earlier this month, Trump similarly unloaded on Christie after the governor dismissed his "ridiculous" plan to temporarily bar Muslim tourists and immigrants from entering the US.

"There are folks in this race who don't care about what the law says because they're used to being able to just fire people indiscriminately on television," Christie said at the time, according to a transcript provided by his campaign.

Christie has surged in recent polls of the first-in-the-nation New Hampshire primary and is banking much of his campaign on doing well there.

"All I have to say to Donald Trump is, 'Happy new year, and I'll see you in New Hampshire,'" Christie said on Tuesday of Trump's attacks, according to The Washington Post. "This is not a game where you're pumping out your chest and saying who's going to be the toughest guy. ... I'm not going to get into a tit for tat with him. I'm bigger and better than that."

EXCLUSIVE FREE SLIDE DECK: The Future of Media by Henry Blodget and the BI Intelligence Research Team.Get the Slide Deck Now »